A fuel cell (FC) has higher energy conversion rate than the conventional batteries and poses no threat to the environment. Its importance is now playing a vital role in the new energy era.
A fuel cell generally converts chemical energy into electricity through a circuit composed by the cathode, the anode and the electrolyte as well as the potential difference between reducible fuel such as hydrogen and oxide gas such as oxygen to undergo a spontaneously oxidation reduction. The byproduct of this oxidation reduction will be water or carbon dioxide (CO2) only so that there is no pollution issue to use this kind of reaction.
Based on ion variation and ion conduction differences, a fuel cell generally is categorized to five different types and among which, the solid oxide fuel cell, SOFC, also called ceramic fuel cell, has the highest reaction rate and requires no activator to undergo the reaction. In addition, the SOFC is available for various fuels and the byproduct, steam, during its reaction is good for steam-power generation industry. The conversion rate for this steam-power generation reaches more than 80% efficiency.
During the use of a solid oxide fuel cell, the fuel containing carbon monoxide (CO) and hydrogen (H2) flows through air paths and diffuses on the surface of the anode. If the distal ends of the air paths are right angles and the fuel in gas type flows through the distal ends, stress at the right angles of the air paths distal ends builds up, which will easily break the distal ends of the air paths due to large concentration of air pressure.
Furthermore, because the electrolyte is sandwiched between the anode and the cathode, while in manufacture, if the distal ends of the air paths are right angles, the distal ends will easy be stress concentrated and eventually cause breakage during curing. Other factors such as differences among material characteristics will too cause the breakage to the distal ends of the air paths during drying and expansion and contraction (cooling process).
As a result of these problems, the most crucial problem to be solved is to create an air path that will disperse the stress both in the manufacture process and in the reaction process.